Advice - Building a fixed gear on the cheap...

I've built a few bikes now. Now I have friends coming up to me asking me to build bikes for them. I'd love to, it's a lot of fun for me. The problem is, I don't feel right asking them to shell out some large amount of money to recycle some crappy old cro-moly frame. I want to be able to build them for CHEAP (less than 100 dollars). I feel like I've got building a fixie on the cheap down to a science. The original cranks, headset, frame, bars, and maybe brakes can be recycled.

re: selling the bikes - No way. I do this for fun and for free. Actually, I usually end up throwing a bit of my own money in. I just like to build bikes for friends. It's rewarding and it gets butts on seats.
re: replacing the bb - I like to. It's much smoother when it's done and it doesn't loosen up. I always get a 107mm because then I can get a nice straight chainline with an inexpensive set of Shimano 600s in the future.
re: just spending 200 on wheels- That's why I'm posting here. I can spend 200 on wheels no problem. It just sucks to ask not so fortunate friends of mine to shell out that kind of money when for less than $150 they could go buy a never used mountain bike that some yuppie around here bought on a whim and never rode. Or maybe a bike like this. http://phoenix.craigslist.org/bik/615735557.html
We're lucky here in Phoenix. Every day dozens of bikes are posted up for sale by people who buy them to hang up in their garage for a year. There's also a lot of serious racers with a lot of money who sell their bikes cheap when they outgrow them. It's great.

I know this is a bit backwards thinking...

sort of takes away the fun of what you want to do, but maybe you can just take the wheels off of these guys and then use the frameset for your own project?

there seem to be a pretty good selection of track/ss wheelsets for sale on ebay. if your friends aren't too concerned with having the best or the fastest, i see no reason why they couldn't make good use of some of the utilitarian listings.

hey tgrssn, are you still building fixed gears on the cheap, and up to date with the market parts and prices? I am trying to help a friend potentially build up a fixie on a cheapie bike and frame. I just have several questions.

Where do you find the lowest price items? a website, local bike shop, more than one website?

Why the UN53 Bottom Bracket? is that the cheapest or best bang for the buck for bottom brackets?
How would the stock BB compare with the UN53, and what do you mean by it loosening up?

Is Bikeisland the cheapest you find a fixed wheelset? They seem to be out of stock at the moment, ya think they will restock quickly or frequently?